Chrome/iOS/Web: There are plenty of services online that track products and sales for you. Where Hukkster excels above the others is that it can keep up with items at the SKU level, following them by size, color, and more.

The service has a Chrome extension as well as an iOS app. Add an item to your watch list (a process unsurprisingly called "Hukking") and you can designate when you want to be notified: when it goes on sale, when it drops in price by 25%, or when it drops by 50%. You can create separate watch lists and organize your products as you please. You can use Hukkster's own interface in the iOS app or on the web, but you can also browse many sites like you normally would. Hukkster already integrates with name brand sites like the Gap or Nordstrom, as well as more commonly used shopping sites like Amazon and Walmart.